var flag = true;

if(flag) {
    console.log("a: flag is true");
}

function sum(num1, num2) {
    return num1 + num2;
}

console.log("a:sum " + sum(10, 20));
//1.导出方式1
export {
    flag, sum
}

//2.导出方式2，导出类/函数
export function mul(num1, num2) {
    return num1 * num2;
}
export class Person {
    run(){
        console.log("run");
    }
}